Method for assembling heat exchangers having flattened tubes



March 18, 1947. r RQSALES 2,417,661

M300 FOR ASSEMBLING HEAT EXCHANGERS HAVING FLATTENED TUBES Filed April 5, 1943 3 Sheets-Sheet 1 3m entot JOSEPH 610054155,

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March 18, l947.- J. G. ROSALES' METHOD FOR ASSEMBLING HEAT EXCHANGERS HAVING FLATTENED TtJBES Filed April 5, 1943 3 Sheets-Sheet 2 Snnentor: Jose- 6. pas/115s,

(Ittomeg Match 18, 1947. J. 5. ROSALES METHOD FOR ASSEMBLING HEAT EXCHANGERS HAVING FLATTENED TUBES 3 Sheets-Sheet 3 Filed Apri1 5, 1943 I T"" IIIIZI Summon: JosrAw 6. 1005/1159,

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Patented 18, 1947 METHOD FOR ASSEDIBLING HEAT nx- CHANGERS HAVING FLATTENED TUBES Joseph G. Itosales, Los Angeles, Calif., assignor to The Garrett Corporation, Alresearch Manufacturing Company division, Los .a corporation of California Angeles, Calif;

Application April s, 1943, Serial No. 481,832

6 Claims. (Cl. 29-1573) My invention relates to the manufacture of heat exchangers for intercoolers having flattened tubes therein, the interiors of which tubes provide passages for one flow of fluid and the exteriors of which define passages for a second flow of fluid in heat exchanging relation to the first flow by reason of the two flows being separated by the thin metal walls of the tubes which conduct heat from one flow to the other.

It is an object of the invention to provide a simple and effective method whereby round tubes may be flattened after they have been arranged in a supporting frame work or housing in suitably spaced relation.

It is a further object of the invention to provide a method of constructing heat exchangers of the type with which this application is concerned wherein a first row of tubes is positioned on an intermediate plane within the housing of the heat exchanger, whereupon these initially placed tubes are flattened, and in which method the heat exchanger is completed by progressively assembling consecutive rows of tubes on opposite sides of the row or bank of tubes which has been installed on the intermediate plane, each row of tubes after placement being flattened before the succeeding taken on the plane indicated by the line 22 of "Fig. l.

T Fig. 3 is a fragmentary partly sectioned plan 'i-view, drawn to enlarged scale, showing my tube flattening means, this figure being sectioned as indicated by the line 33 of Fig. 4. {1f Fig. 4 is a sectional view taken as indicated by the line 4-4 of Fig. 3, with parts of the plate ofthe device sectioned so as to show the fixed and lmovable jaws which project from the plate or jaw supporting member.

Fig. 5 is a fragmentary sectional view showing "the manner in which the tubes are expanded adjacent a'plate. In Fig. 1 of th drawings 1 show a simple form of intercooler made in accordance with my invention. This intercooler comprises a housing or frame structure Ill having spaced header plates plates H and I2 to form a rectangular passage l5 extending from the front l6 tothe rear" 01! the intercooler. An intermediate wall or plate I8 is supported by the walls 13 and I4 in a position between the plates II and I2. Flattened tubes l9 are extended across the passage IE of the intercooler.

The plates I I, I2 and ill have therein cooper ating holes 20 to receive portions of the tubes it, these openings 20 being disposed in planes which extend in transverse relation to the longitudinal axis of the passage I5 and preferably perpendicular to the plates ll, l2, and I8 of the walls l3 and It. These planes are spaced in parallel relation from the front to the rear of the passage Iii. One of such planes I have indicated as the intermediate plane rt-a in Fig. l, for the reason that in the preferred practice of the invention the oper- As shown in Fig. 2, the openings 2b in one plane, such as the plane 0-0;, are in staggered or offset relation to the openings 20 in the planes adjacent thereto, for example, the planes h-b. The tubes are flattened, between the plates ll, l2, and I 8 to somewhat elliptical form and so that the greatest dimension of the flattened portions of these tubes will be perpendicular to the planes a,a'and bb. The tubes l9, thus flattened, define air flow passages 2| from the front to the rear of the major passage 15 defined by the housing it. v

The flattening of the tubes I9 is accomplished by use of the flattening tool shown in Figs. 3 and 4 after each set of tubes is placed in the cooperating openings 20 in a transverse plane of the intercooler structure. The tube flattening tool includes a support 22 of rectangular form, as shown in Fig. 4', and having an opening 23 near the center thereof. A plurality of fixed jaw members 24 project from the front face of the support 22 in parallel relation. These jaw members 24 are preferably formed integrally with the support 22 and comprise relatively narrow walls of blade-like form "extending the full width of the support 22 as shown in Fig. 4.

ll and it connected and supported by spaced Aligned openings 25 extend through the jaw 3 members 24 so as to receive bar means 24 adapted to support movable jaw members 21 in cooperative relation to the fixed jaw members 24. There are two of the bar means 28, and each of these comprises a screw 28 having a cylindric head 29,

- a long shank 20 and a short threaded end ii.

. 34 to' receive the threaded ends 3| of the screws 28. The heads 24 of the screws 24 havesockets 34 therein engageable by a wrench whereby the screws 28 may be turned so as to advance the threaded ends 2| thereof in the threaded openings and thereby clamp the assembly of jaw members 21 and sleeves 22 rigidly between the heads 29 of the screws 24 and the end movable jaw member 21'.

The support 22 carries means operable to move the jaw members 21 toward the flxed jaw members 24. Such means consist of a lever 36 swingable in the pening 22 on a transverse pin 31, with the forward end 38 of this lever being positioned so as to engage the back face 39 of a movable jaw member 21, The rear end 40 of the lever 28 projects from the opening 24 and is engageable by a lever 4| through which force may be transmitted to rotate the lever 36 in such direction that the front end 38 thereof will move the jaw member 21 thereby engaged toward the stationary or fixed jaw member 24 with which it cooperates, such movement being transmitted through the bar means 26 to the entire assembly of movable jaw members 21 so that they will all be simultaneously moved toward the cooperating fixed jaw members 24.

A' supporting arm 42- is secured by screws 43 to the rear face of the support 22 in approxi- .mately parallel relation to the lever 4|, and

through thi supporting arm 42 an adjusting screw 44 is extended. The end 45 of the screw 44 confronts the back face 46 of the rear end 40 of the lever 36, and limits the movement of the lever 46 by the actuating lever 4|. A spring 41 is disposed around the end 45 of the screw 44, between the arm 42 and the lever 36, to move the lever 36 so as to return the movable jaw members 21 to open positionrelative to the fixed jaws,

24.- The jaw members 24 and 21 are chamfered so as to give to them such thinness that they will enter the spaces between tubes. 19, as shown vin Fig. 3, and shoulders 48 are provided to engage the edge portions of tubes. which have been previously flattened. It will be noted that the ooflattened thereby in the manner described in the preceding paragraph. The flattened tubes IS in the first'set positioned in the plane (1-0, are shown in Fig. 3. Thereafter sets of tubes it are placed in the cooperating openings in the planes b-b adjacent the plane H, and the flattening tool is employed as shown in Fig. 3 to flatten these additional sets of tubes. It will be understood that the tool will be first inserted into the front open end of the structure to flatten the set of tubes in one of the planes b-b, and will be inserted through the rear opening of the structure to flatten the tubes of the second set of tubes on the remaining plane b -b. After completion of the foregoing, two more sets of tubes will be simultaneously placed by two workers adjacent the sets of tubes last previously flattened, and these newly placed sets of tubes will be then flattened in the manner described. This process of placing the tubes will be repeated until the holes 20 in the plates ll, 12, and I8 are all filled.

The flattening of the tubes is carried relatively close to the supporting plates, and particularly the intermediate plate I, so that the deformation of these tubes will arrange portions thereof in positions to prevent lateral movement of the plate I! and substantially minimize vibration thereof. In Fig. 5 I show a portion of a tube is passing through a hole 20 in the intermediate plate It. Adjacent the plate l8, the tube I9 is flattened as indicated at 50. The flattening of the tube results in the formation of sloping portions 5| which start at the extremities of the holes 20 and expand outwardly. In even a small intercooler there may be several thousand of these sloping portions on each side of the intermediate plate to act as shoulders which will limit or restrain movement of the plate in a direction perpendicular to the side faces thereof, the result being that the flattened tubes act to prevent vibration of the intermediate wall l8. At the same time a binding of the tubes IS in the openings 20 of the intermediate plate 18 is produced so that there is a restraint on vibration of the tubes. The ends of the tubes I! are locked in the holes 20 of the header plates II and I2 by expanding the tubes within the openings or by expanding ,metal ferrules in the end openings of the tubes.

' front to rear, comprising: placing a set of tubes operating pairs of jaws, each pair consisting of a jaw 24 and a jaw 21, engage alternating tubes It in the row of tubes to be flattened. Actuation of the tool will flatten these alternate tubes, after which the tool is shifted so as to be applied to the remaining unflattened tubes.

In the preferred practice of my method of constructing a heat exchanger having flattened tubes a set of tubes is installed in the cooperating holes 20 in the intermediate plane 0-11. The tubes,

when so placed, have their end portions resting in holes in the header plates I I and I2, and intermediate portions thereof passing through cooperating holes in the intermediate plate l8. The flattening tool is then passed into the upper and lower sections of the passage i5 from one end of the structure l0 and the tubes of the first set are in an intermediate row of holes; subsequently flattening simultaneously one group of tubes in said set; subsequently flattening simultaneously another group in said set; continuing said flattening operation until all of the tubes of said set are flat; subsequently and progressively placing additional sets of tubes in rows of holes adjacent a. previously flattened row of tubes; and repeating the flattening operation on such subsequently placed rows of tubes before placing a succeeding row of tubes in front thereof.

2. The steps in a method of assembling and flattening round tubes in a cooler frame structure having spaced header plates with holes therein arranged in rows disposed in consecutive planes from front to rear, comprising: placing a set of tubes in one of said rows of-holes; flattening all of the tubes in said row in a plurality of flattening operations in each of which a plurality of said tubes are simultaneously flattened; subsequently and progressively placing tubes in the remaining rows of openings; and repeating the flattening operation on each row of tubes before placing another row in front thereof.

3. The steps in a method of assembling and flattening round tubes in a cooler frame structure I having spaced header plates with holes therein arranged in rows disposed in consecutive planes from front to rear, comprising: placing tubes in one of said rows of holes; flattening all of said tubes in at least two flattening operations in which a plurality of said tubes are simultaneously flattened;' subsequently placing tubes in a row adjacent said flattened row of tubes and repeating the flattening operation thereon; and continuing the placement of tubes and the flattening of the tubes thus placed in consecutive rows until all of the tubes are flattened.

4. The steps in a method'of assembling and flattening round tubes in a cooler frame structure having spaced header pla'tes provided with rows of holes arranged in consecutive planes from front to rear, comprising: placing a plurality of tubes in each row of holes and flattening the tubes in each row in a number of flattening operations in each ofwhich a plurality of tubes are simultaneously flattened, the placing and flattening operations being so related to each other that all of the tubes in one row are flattened before the tubes in the next adjacent row are placed.

5. A method of assembling and flattening round tubes in a cooler frame structure having spaced header plates provided with rows of holes arranged in consecutive planes from front to rear, comprising: consecutively placing sets of tubes in the respective rows of holes; flattening alternate tubes in each row in one flattening operfront to rear, comprising: installing tubes in one row of holes; flattening, in a simultaneous flat tening operation, a group comprising at least a plurality of alternate tubes of said row; subsequently flattening another group comprising tubes intermediate said alternate tubes; placing tubes in a row of holes adjacent said one row of holes containing said flattened tubes, after the latter have all been flattened; and repeating the flattening operation on said subsequently placed tubes.

JOSEPH G. ROSALES.

REFERENCES CITED The following references are 01 record in the file of this patent:

UNITED STATES PATENTS Date Ramsaur July 7, 1942 

